|epizootics||5/19/2017 2:52 AM|
|help with a jazzmaster/P-90 hybrid|
This will be my first post here even though I have been reading this forum for quite a while now.
This will not be the first pickup I build, but pretty close. So far, I only have made a couple of Dano lipstick-inspired pickups that sound pretty close to what I was aiming - Vocaroo | Voice message .
I like slightly atypical pickups - my idea of a good tone is a super-bright, slightly aggressive sound (think Television, Robert Quine and Arto Lindsay).
I'm looking at making two pairs of the aforementioned hybrid, one for a friend's strat and one for a guitar I'm building at the minute. The only close thing I found on the market is the Manlius Goatmaster, ie. a P-90 with alnico poles instead of the two bar magnets/spacer design. The reasons for this choice are both economical and practical: bar magnets are more expensive and harder to source than alnico poles 'round my parts (Lyon, France), and although I like the sound of a typical P-90, I am also a big fan of the extra brightness of those JM pickups. That Goatmaster is pretty close to what I'm after.
Considering the scarcity of vulcanized fiber in France and the high costs of importing it from the US, I tried a lot of different materials for the flatworks and found that old vinyl records were a good compromise - not too brittle, not too flexible, easy on the tools and really, really cheap.
So. I have a 500g spool of AWG 42 and a bunch of alnico 5 poles that are 5mm thick and 16mm long. Bobbin height is going to be 6mm, and the flatwork is 80x29x1.24mm. I usually like the sound of low output pickups and I'm thinking in the area 8000 winds.
Also, I was thinking of having the top of the poles flush against the top of the flatwork, in order to have the bobbin itself closer to the strings. For aesthetic reasons, I also planned on cutting the plastic cover in a diamond shapes and stick some red velvet on the top of the pickup.
Does this sound reasonable? I'll try to make a schematic of all this, complete with imperial measurements...
|big_teee||5/19/2017 6:36 AM|
Though a world wide forum, pickup data is usually given in inches decimal.
Maybe some of the other non North American guys can help you.
|epizootics||5/19/2017 8:07 AM|
|I thought it would be! I'm getting used to switching from one to the other since most of the online ressources are in inches. I'm sure you guys feel the same way about millimeters, aha.|
Here is the schematic. Sorry for my poor CAD skills!
|big_teee||5/19/2017 9:13 AM|
|Here's a similar JM bobbin, dimensions, and data.|
If you can give specific internal bobbin dimensions, I can work up data for your pickup.
|big_teee||5/19/2017 10:34 AM|
|Here's what your pickup data may look like.|
**BTW, I would'nt make the top magnets completely flush.
I would leave a little sticking out the top, in case you have any flaring, so the magnets don't slip out of the top flatwork.
|epizootics||5/19/2017 12:07 PM|
|Thank you very much for those numbers! |
Just to make sure - is flange the part of the flatwork at the bottom that sticks out, like on a typical Strat pickup? If so, there isn't any on my design - I drilled two extra tiny holes on the bottom plate near the external side, through which I tie two small sections of copper wire. I then heat the surface with a lighter and gently press them down to flatten the surface and to avoid the coils from catching on them. A cheap alternative to eyelets, which would be a pain to fit onto the vinyl anyway.
So, looking at the numbers, I assume 6.6K gives me an indication of the resistance I should be aiming at with the type of sound I am after?
I'm getting a bit better at keeping tension constant on my makeshift setup, which consists in my old reliable drill, a wire counter made from an old calculator and a homemade traverse limiter. I would assume I fall in between "loose" and "tight scatter". Would 7500 turns be about right?
Thanks again for your help, and more generally to everybody on this board for making this incredible amount of information and inspiration available...
|big_teee||5/19/2017 12:28 PM|
|The Flange is the width of the bobbin flatwork at the narrowest part.|
Usually that is the top bobbin flatwork.
Wound to the flange width, would be the most wire you could put on it, without hanging off the bobbin.
I usually wind at around 90 percent, and that is where I saw 8000 turns or so.
That is just a ballpark chart of what to expect.
If you want 8000 turns, The Chart shows you should have plenty of room to wind that many.
If you wind looser, you will just wind up with a little higher DCR than 6600 ohms at 8000.
|epizootics||5/19/2017 12:39 PM|
|Ah, I see what you mean. Sorry, this is all new terminology in English for me (not that we have satisfying equivalents in French, come to think of it)...|
Both the flatworks are the same size, as on your regular p90. Thanks for the warning about flaring too!
So, looking at the relatively low DCR, would it be relevant to increase the bobbin height a wee bit, or would that be fitting what I'm after? Keeping in mind that DCR isn't everything of course.
|big_teee||5/19/2017 1:00 PM|
|With all things equal, taller and narrower coil bobbin height, usually makes the pickup brighter.|
Shorter and wider coil makes the pickup sound fatter, or darker.
Fender with strats and teles, do taller and brighter.
Jazz Master, and P90 does the short and wide coil.
I would think .24-.30 inches tall would be a good compromise between strat and P90 tones.
Experiment and see what you come up with.
Anyone else want to jump in, please do!
|copperheadroads||5/20/2017 10:39 AM|
|If your new to winding I wouldn't go with the vintage Jazzmaster height of about 3/16" as it's one of the trickiest pickups to get right without much wire to waste ,& suggest as already suggested going with a little taller like a p-90 .250"|
|epizootics||5/20/2017 4:16 PM|
|Yup, I did attempt to wind one of these as my first project...The only wire I had for this one was AWG 43 from another pickup (!) I'd stuck on a spool on top of my wife's sewing machine, and a dodgy round plate adapted to a dodgy hand drill and no traverse limiter. Needless to say, I broke a lot of wire. It was good schooling though - I almost got a couple thousand winds in one of my attempts, which I now realize was pretty impressive looking at my setup.|
I'll start winding early next week, I'll keep you guys updated...Thanks again for your answers!
|epizootics||5/22/2017 8:58 AM|
|Ok guys, here goes...|
I made a quick sample of what it sounds like in context (mounted sans cover on my Blade Durango) as I'm not a big fan of guitar sounds by themselves:
(sorry for my shoddy playing!)
DCR reading says 6.45K. Something went wrong with my wire counter, it got lost on the way it seems. Final reading was in the area of the 4000s but by the look of the bobbin, it was quite a bit more than that. I need to address that problem.
I got pretty much what I wanted - mean but meatier than a regular strat pickup. Three more to go! Thanks again for your help...